<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        function fn() {
            console.log('fn');
        }
        fn();

        const fn2 = function() {
            console.log('fn2');
        }
        fn2();

        const fn3 = new Function('console.log("fn3")');
        fn3();

        const fn4 = new Function('a', 'b', 'console.log(a + b)');
        fn4(10, 20);
        console.log(fn4);

        console.dir(function fn(){});
    </script>
</body>
</html>